Remarkable effect was achieved in exploration mineral resources using the multispectral remote sensing alteration anomalies. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) data, one of multispectral data, offered by China Remote Sensing Satellite Ground Station in July,2004.Being wider wavelength ( VNIR (Visible and Near Infrared), SWIR (Short wavelength Infrared) and TIR (Thermal Infrared)), more wave bands (14 bands) and reasonable ratio of capability with price, ASTER data have been developed rapidly. For a long time, remote sensing information extraction of alteration anomalies in thin overburden areas is a technodifficulty. This paper has described the alteration anomalies information in thin overburden areas, Baoguto porphyry copper deposits intrusions (No. 2 and No. 5) in western Junggar, Xinjiang, by ASTER data. The alteration anomaly information shows well consistence with the filed geological survey. Two groups alteration, with distinct different in characteristic spectrum band, have been extracted. The first group includes montmorillonite, halloysite, illite and sericite and the second includes calcite, biotite and chlorite. Anomaly targets have been put forward for advance study at last.